The aim of this project has been to achieve effective therapeutic control of spontaneous and transplantable leukemias and lymphomas. The therapeutic measures encompass drug therapy, surgery, vaccines and non-specific immune stimulators (e.g. BCG and Corynebacterium parvum) used alone or in combination against viral-associated transplantable tumor lines. Results indicate that the use of these "immunopotentiators" (i.e. C. Parvum) to augment the immune response was capable of demonstrating both therapeutic and prophylactic effects against a transplantable guinea pig leukemia (L2C) when administered in the presence of the immunogen. Various procedures (i.e. delayed cutaneous hypersensitivity to soluble antigens, blastogenic responses and lymphokine production), to determine the extent of drug suppression in animals following chemotherapy with cytoxan have demonstrated significant levels of immunocompetence as early as 8 days following drug cessation. Standard in vitro techniques have been employed to monitor the immune response of treated animals to answer whether cell-mediated and humoral immune assays can be used to determine fluctuations in the tumor immune response of animals following treatment with drugs or surgery used alone or in combination with immune stimulators. Attempts to demonstrate host immunity against autochthonous tumors have met with partial success when measuring the production of a "migration inhibition factor" (MIF).